Useful, free resources for SQL Server

Recently Dave Ballantyne posted a list of free resources for SQL Server, entitled "The best things in life are free."  Now, I'm not trying to upstage Dave, but I know of several resources that aren't on his list.  It would be good to have a true community page for this kind of thing, but for now a blog post will have to do.  [I also just re-noticed Mladen Prajdic's post on free SQL Server tools,